Warren is registered as a mediator with the United States District Court for the Middle District of Florida (Tampa, Orlando, Ocala, Fort Myers and Jacksonville Divisions).  He is also certified as a Circuit Civil Mediator by the Supreme Court of Florida.

In 1995, on behalf of the Executive Office for United States Attorneys and in the wake of Attorney General Janet Reno's Order that U.S. Attorney's Offices nationwide make broader, appropriate use of alternative dispute resolution, Warren drafted the original guidelines by which U.S. Attorney's Offices identified cases appropriate for mediation.  He was later recognized by the Department of Justice's Senior Counsel for Alternative Dispute Resolution for his contributions in training Assistant U.S. Attorneys in mediation advocacy and professionalism.